A Rapid Method for Assessing the Environmental Performance of Commercial Farms in the Pampas of Argentina

The generation of reliable updated information is critical to support the harmonization of socio-economic and environmental issues in a context of sustainable development. The agro-environmental assessment and management of agricultural systems often relies on indicators that are necessary to make sound decisions. This work aims to provide an approach to (a) assess the environmental performance of commercial farms in the Pampas of Argentina, and (b) propose a methodological framework to calculate environmental indicators that can rapidly be applied to practical farming. 120 commercial farms scattered across the Pampas were analyzed in this study during 2002 and 2003. Eleven basic indicators were identified and calculation methods described. Such indicators were fossil energy (FE) use, FE use efficiency, nitrogen (N) balance, phosphorus (P) balance, N contamination risk, P contamination risk, pesticide contamination risk, soil erosion risk, habitat intervention, changes in soil carbon stock, and balance of greenhouse gases. A model named Agro-Eco-Index was developed on a Microsoft-Excel support to incorporate on-farm collected data and facilitate the calculation of indicators by users. Different procedures were applied to validate the model and present the results to the users. Regression models (based on linear and non-linear models) were used to validate the comparative performance of the study farms across the Pampas. An environmental dashboard was provided to represent in a graphical way the behavior of farms. The method provides a tool to discriminate environmentally friendly farms from those that do not pay enough attention to environmental issues. Our procedure might be useful for implementing an ecological certification system to reward a good environmental behavior in society (e.g., through tax benefits) and generate a commercial advantage (e.g., through the allocation of green labels) for committed farmers.     

Characterisation of Selected Lentic Habitats of Dharwad, Haveri and Uttar Kannada Districts of Karnataka State, India

Water quality survey was undertaken to study the current status of water quality of some lentic habitats of Dharwad, Haveri and Uttar Kannada districts, to provide a baseline data, comprising study of their main physical and chemical characteristics and also to evaluate the recent limnological changes those have occurred over a time period in some lentic habitats. Trophic status was also analysed. Present study reveals that Unkal lake, and B.K. Shigigatti tank of Dharwad district, Timmapur, Hosalli, and Krishnapur tanks of Haveri district are fast progressing towards hypereutrophication. Of the other tanks, Galgi tank of Dharwad district, Gudgur, Hanamapur, Medleri, and Kadkol tanks of Haveri district have reached the eutrophic stage. The anthropogenic activities, sewage and fertilizers used in agricultural fields appear to be the major causes of the eutrophication in these tanks. If the habitats have to be preserved for their intended use, sustainable and holistic management measures for the remediation of the tanks are an immediate necessity.     

A Characterization of Selected Endocrine Disruptor Compounds in a Portuguese Wastewater Treatment Plant

Anthropogenic compounds that are able to disrupt the endocrine system of wildlife species are a major cause for concern and have led to a demand for new screening methods. The identification and quantification of endocrine disruptor compounds at wastewater treatment plant is of major interest to assess the endocrine activity of wastewater treatment plant discharges into the environment. This study consists of a preliminary survey of concentrations of previously selected endocrine disruptor compounds, undertaken to establish environmental concentrations and to support a biological program assay exposing freshwater fish to them. Selected endocrine disrupting chemicals (APEs, bisphenol A and 17 β-estradiol) were measured in samples from a wastewater treatment plant located in Lisbon (Portugal), using recent commercial enzyme-linked immunosorbent assay kits and also LC-MS/MS. The results show that the wastewater treatment plant treatment process is efficient on the removal of target endocrine disruptor compounds. However, environmentally significant concentrations are still present in the treated effluent. The results also show that enzyme-linked immunosorbent assay kit is suitable for routine analysis of the selected compounds. The results are also useful since the wastewater treatment plant is located in a Mediterranean region, which results in an effluent with its own characteristics.     

Biomonitoring in the Boulder River Watershed, Montana, USA: Metal Concentrations in Biofilm and Macroinvertebrates, and Relations with Macroinvertebrate Assemblage

Portions of the Boulder River watershed contain elevated concentrations of arsenic, cadmium, copper, lead, and zinc in water, sediment, and biota. We measured concentrations of As, Cd, Cu, Pb, and Zn in biofilm and macroinvertebrates, and assessed macroinvertebrate assemblage and aquatic habitat with the objective of monitoring planned remediation efforts. Concentrations of metals were generally higher in downstream sites compared with upstream or reference sites, and two sites contained metal concentrations in macroinvertebrates greater than values reported to reduce health and survival of resident trout. Macroinvertebrate assemblage was correlated with metal concentrations in biofilm and macroinvertebrates. However, macroinvertebrate metrics were significantly correlated with a greater number of biofilm metals (8) than metals in invertebrates (4). Lead concentrations in biofilm appeared to have the most significant impact on macroinvertebrate assemblage. Metal concentrations in macroinvertebrates were directly proportional to concentrations in biofilm, indicating biofilm as a potential surrogate for monitoring metal impacts in aquatic systems.     

Biogeochemical consequences of a changing Arctic shelf seafloor ecosystem

Unprecedented and dramatic transformations are occurring in the Arctic in response to climate change, but academic, public, and political discourse has disproportionately focussed on the most visible and direct aspects of change, including sea ice melt, permafrost thaw, the fate of charismatic megafauna, and the expansion of fisheries. Such narratives disregard the importance of less visible and indirect processes and, in particular, miss the substantive contribution of the shelf seafloor in regulating nutrients and sequestering carbon. Here, we summarise the biogeochemical functioning of the Arctic shelf seafloor before considering how climate change and regional adjustments to human activities may alter its biogeochemical and ecological dynamics, including ecosystem function, carbon burial, or nutrient recycling. We highlight the importance of the Arctic benthic system in mitigating climatic and anthropogenic change and, with a focus on the Barents Sea, offer some observations and our perspectives on future management and policy.     

Kinetics and thermodynamic studies of Methyl Orange removal by polyvinylidene fluoride-PEDOT mats

We report the preparation of poly(3,4-ethylene dioxythiophene) (PEDOT)-modified polyvinylidene fluoride electrospun fibers and their use as a novel adsorbent material for the removal of the anionic dye Methyl Orange (MO) from aqueous media. This novel adsorbent material can be used to selectively remove MO on a wide pH range (3.0–10.0), with a maximum capacity of 143.8 mg/g at pH 3.0. When used in a recirculating filtration system, the maximum absorption capacity was reached in a shorter time (20 min) than that observed for batch mode experiments (360 min). Based on the analyses of the kinetics and adsorption isotherm data, one can conclude that the predominant mechanism of interaction between the membrane and the dissolved dye molecules is electrostatic. Besides, considering the estimated values for the Gibbs energy, and entropy and enthalpy changes, it was established that the adsorption process is spontaneous and occurs in an endothermic manner. The good mechanical and environmental stability of these membranes allowed their use in at least 20 consecutive adsorption/desorption cycles, without significant loss of their characteristics. We suggest that the physical-chemical characteristics of PEDOT make these hybrid mats a promising adsorbent material for use in water remediation protocols and effluent treatment systems.     

Pilot project of mechanical-biological treatment of waste in Brazil

By mechanical-biological treatment (MBT) of residual municipal solid waste the behaviour of landfills can be significantly improved. After MBT the organic content (COD and BOD5), total organic carbon, and total nitrogen in the leachate, as well as the gas production rate, are reduced to values lower than 90% of the fresh untreated waste. The volume of the stabilized material to be disposed on landfills decreases enormously, by up to 70%. The monitoring effort for a landfill constructed under these conditions is reduced to a minimum and the stabilized material can be used in other ways, as material for reforestation, for cover material or for thermal utilization to produce energy. Environmental conditions are important in MBT, as well as waste characteristics. This paper describes the results of a pilot project of MBT performed in Rio de Janeiro, Brazil. The results have shown that this technology can be used successfully in developing countries, with economy for the society and important results for the environment.     

Mechanical-biological waste treatment and the associated occupational hygiene in Finland

A special feature of waste management in Finland has been the emphasis on the source separation of kitchen biowaste (catering waste); more than two-thirds of the Finnish population participates in this separation. Source-separated biowaste is usually treated by composting. The biowaste of about 5% of the population is handled by mechanical-biological treatment. A waste treatment plant at Mustasaari is the only plant in Finland using digestion for kitchen biowaste. For the protection of their employees, the plant owners commissioned a study on environmental factors and occupational hygiene in the plant area. During 1998-2000 the concentrations of dust, microbes and endotoxins and noise levels were investigated to identify possible problems at the plant. Three different work areas were investigated: the pre-processing and crushing hall, the bioreactor hall and the drying hall. Employees were asked about work-related health problems. Some problems with occupational hygiene were identified: concentrations of microbes and endotoxins may increase to levels harmful to health during waste crushing and in the bioreactor hall. Because employees complained of symptoms such as dry cough and rash or itching appearing once or twice a month, it is advisable to use respirator masks (class P3) during dusty working phases. The noise level in the drying hall exceeded the Finnish threshold value of 85 dBA. Qualitatively harmful factors for the health of employees are similar in all closed waste treatment plants in Finland. Quantitatively, however, the situation at the Mustasaari treatment plant is better than at some Finnish dry waste treatment plants. Therefore is reasonable to conclude that mechanical sorting, which produces a dry waste fraction for combustion and a biowaste fraction for anaerobic treatment, is in terms of occupational hygiene better for employees than combined aerobic treatment and dry waste treatment.     

Effect of temperature and organic nutrients on the biodegradation of linear alkylbenzene sulfonate (LAS) during the composting of anaerobically digested sludge from a wastewater treatment plant

Limits on the application of biosolids (anaerobically processed sludges from wastewater treatment plants) as fertilizers for the amendment of soil are becoming greater because of the accumulation of recalcitrant substances, making necessary the use of techniques that bring the concentration of xenobiotics to lower concentrations than those permitted. In general, the biosolids composting process is sufficient to reduce the usual concentration of linear alkylbenzene sulfonates (LAS) to low levels. In this work, an assessment is made on the effect of temperature in the capacity of enriched bacterial populations to biodegrade LAS, together with the influence that the available nutrients may have in the biodegradation of these compounds. The results show that the microbial metabolism of LAS was not observed in the thermophilic range. The optimum temperature for the biodegradation of LAS appears to be around 40 degrees C, this is, the lowest assayed here, and at this temperature the differences in the biodegradation of LAS among the nutritionally supplemented cultures are small.     

Effects of the forced ventilation on composting of a solid olive-mill by-product ("alperujo") managed by mechanical turning

The evaluation of the most suitable aeration technology for olive-mill by-product "alperujo" (AL) composting was carried out by using two identical piles prepared by mixing AL with a bulking agent (fresh cow bedding) and a mature compost (as inoculant). Forced ventilation was employed in conjunction with mechanical turning in one of the piles, whereas only mechanical turning was used in the other pile. These two treatment methods were evaluated by assessing process efficiency and end-product quality. The results show that the composting process was completed in less time when forced ventilation was coupled with mechanical turning. A slight delay in the evolution of pH, C/N ratio, and biodegradation of fats and organic matter was observed when only turning was employed. However, the recommended method for composting AL was mechanical turning without forced ventilation since the composition of the end-product in this case was comparable to the composted AL using forced ventilation coupled with mechanical turning. Furthermore, there were substantial economic savings by selecting mechanical turning alone, which included capital costs for equipment.